A dual polarised horn with a scanning beam

The proposed antenna is a special type of multibeam antenna (MBA). The unique feature of this particular antenna is that beam scanning is achieved within the confines of a single horn. The additional advantages of compactness and high gain are clearly evident in this design. The antenna described is a compact quad-ridged horn. Each ridge in the horn is fed separately at four orthogonal inputs to a square waveguide. By means of an RF network consisting of a number of 180 degrees Hybrids and delay lines, the beam of the horn can be switched in azimuth over 110 degrees. The nominal gain of the horn is more than 8 dBi. The aperture size is about 0.6×06 wavelengths at the low end of the band. The length of the antenna is less than three quarter of a wavelength at the low end. The antenna is extremely rugged and is designed to operate under severe environmental conditions